Therapeutic effects of BYK-1 in GVHD induced by MHC-matched, minor histocompatibility antigen-mismatched BMT. On day 0, B6 recipient mice were exposed to lethal irradiation (12 Gy) and transferred intravenously with 5 × 106 T cell-depleted BM cells together with 3 × 106 spleen plus lymph node cells isolated from C3H.SW donor mice. The recipient mice were treated intraperitoneally with 200 μg BYK-1 (▲) or control Ig (●) every 5 days from day 0 to day 25. As non-GVHD control, a group of mice were transferred with T cell–depleted BM cells alone (○). Survival of recipient mice (A), changes in body weight (B), and GVHD clinical scores (C) were monitored after BMT. (D) Pathologic features of recipient liver and skin were examined by hematoxylin and eosin staining (original magnification ×400 in the liver and ×100 in the skin). (E) Spleen cells of the recipient mice that had survived GVHD more than 100 days by BYK-1 treatment were assessed for the expression of Ly9.1 (donor cell marker) and CD3 or B220 by flow cytometry. Data are representative of 3 independently repeated experiments (n = 5 per group).
